This paper focuses on implementing differential evolution (DE) to optimize the robotic assembly line balancing (RALB) problems with an objective of minimizing energy consumption in a straight robotic assembly line and thereby help to reduce energy costs. Few contributions are reported in literature addressing this problem. Assembly line balancing problems are classified as NP-hard, implying the need of using metaheuristics to solve realistic sized problems. In this paper, a well-known metaheuristic algorithm differential evolution is utilized to solve the problem. The proposed algorithm is tested on benchmark problems and the obtained results are compared with current state. It can be seen that the proposed DE algorithm is able to find a better solution for the considered objective function. Comparison of the computational time along with the cycle time is presented in detail. © Springer International Publishing AG 2018.